Martijn van de Giessen

• MSc. PhD.
• Leiden University Medical Centre

With almost 50% of all surgeries in the U.S. being performed as minimally invasive procedures, there is a need to develop quantitative endoscopic imaging techniques to aid surgical guidance. Recent developments in widefield optical imaging make endoscopic implementations of real-time measurement possible. In this work, we introduce a proof-of-conce...

Background: The purpose of our study is to develop the arthroscopic autofluorescence imaging (AFI) system to improve the visualization during arthroscopic surgery by real-time enhancing the contrast between joint structures with autofluorescence imaging. Its validity was evaluated around the arthroscopic anterior cruciate ligament (ACL) reconstruc...

Mild Cognitive Impairment (MCI) is an intermediate stage between healthy and Alzheimer's disease (AD). To enable early intervention it is important to identify the MCI subjects that will convert to AD in an early stage. In this paper, we provide a new method to distinguish between MCI patients that either convert to Alzheimer's Disease (MCIc) or re...

Background Evaluation of resection margins during cancer surgery can be challenging, often resulting in incomplete tumour removal. Fluorescence-guided surgery (FGS) aims to aid the surgeon to visualize tumours and resection margins during surgery. FGS relies on a clinically applicable imaging system in combination with a specific tumour-targeting c...

Objective: The etiology of osteochondral defects (OCDs), for which the ankle (talocrural) joint is one of the common sites, is not yet fully understood. In this study, we hypothesized that bone shape plays a role in development of OCDs. Therefore, we quantitatively compared the morphology of the talus and the distal tibia between an OCD group and...

With 50% of all interventional procedures in the US being minimally invasive, there is a need for objective tools to help guide surgeons in this challenging environment. Tissue oxygenation is a useful biomarker of tissue viability and suitable for surgical guidance. Here we present our efforts to perform real-time quantitative optical imaging throu...

A novel acquisition and processing method that enables real-time, single snapshot of optical properties (SSOP) and 3-dimensional (3D) profile measurements in the spatial frequency domain is described. This method makes use of a dual sinusoidal wave projection pattern permitting to extract the DC and AC components in the frequency domain to recover...

Preoperative imaging of the cerebral vessel tree is essential for planning therapy on intracranial stenoses and aneurysms. Usually, a magnetic resonance angiography (MRA) or computed tomography angiography (CTA) is acquired from which the cerebral vessel tree is segmented. Accurate analysis is helped by the labeling of the cerebral vessels, but lab...

Alzheimer's disease (AD) is one of the most frequent forms of dementia and an increasing challenging public health problem. In the last two decades, structural magnetic resonance imaging (MRI) has shown potential in distinguishing patients with Alzheimer's disease and elderly controls (CN). To obtain AD-specific biomarkers, previous research used e...

The cohort size required in epidemiological imaging genetics studies often mandates the pooling of data from multiple hospitals. Patient data, however, is subject to strict privacy protection regimes, and physical data storage may be legally restricted to a hospital network. To enable biomarker discovery, fast data access and interactive data explo...

Minimally invasive surgeries are approaching 50% of all interventional procedures in the US, yet there is a lack of objective tools to assist surgeons in this limited sensing environment. In this preliminary work, we present a novel proof of concept implementation of Single Snapshot of Optical Properties (SSOP) imaging through a rigid endoscope. In...

Wide-field optical tissue characterization has a large clinical potential that is currently not exploited due to the lack of realtime imaging methods. In this work we propose 3D single shot optical properties imaging (3D-SSOP) a new acquisition and processing method for obtaining surface profile corrected tissue absorption and reduced scattering co...

Excision of the whole tumor is crucial, but remains difficult for many tumor types. Fluorescence lifetime imaging could be helpful intraoperative to differentiate normal from tumor tissue. In this study we investigated the difference in fluorescence lifetime imaging of indocyanine green coupled to cyclic RGD free in solution/serum or bound to integ...

Wide-field oxygenation saturation (StO2) estimates can be clinically very advantageous. Particularly when implemented in a non-contact manner, applications such as intra-operative assessment of tissue perfusion are very promising. Nevertheless, wide-field optical oxygenation imaging did not yet successfully translate to the clinic. In this work we...

Diffuse optical spectroscopy (DOS) may be advantageous for monitoring tumor response during chemotherapy treatment, particularly in the early treatment stages. In this paper we perform a second analysis on the data of a clinical trial with 25 breast cancer patients that received neoadjuvant chemotherapy. Patients were monitored using delayed contra...

Purpose: Diffuse optical spectroscopy (DOS) has the potential to enable monitoring of tumor response during chemotherapy, particularly in the early stages of treatment. This study aims to assess feasibility of DOS for monitoring treatment response in HER2-negative breast cancer patients receiving neoadjuvant chemotherapy (NAC) and compare DOS with...

Purpose: Near-infrared (NIR) fluorescence imaging can provide the surgeon with real-time visualization of, e.g., tumor margins and lymph nodes. We describe and evaluate the Artemis, a novel, handheld NIR fluorescence camera. Procedures: We evaluated minimal detectable cell numbers (FaDu-luc2, 7D12-IRDye 800CW), preclinical intraoperative detecti...

The Allen Brain Atlases enable the study of spatially resolved, genome-wide gene expression patterns across the mammalian brain. Several explorative studies have applied linear dimensionality reduction methods such as Principal Component Analysis (PCA) and classical Multi-Dimensional Scaling (cMDS) to gain insight into the spatial organization of t...

Compressed sensing (CS) magnetic resonance imaging (MRI) enables the reconstruction of MRI images with fewer samples in k-space. One requirement is that the acquired image has a sparse representation in a known transform domain. MR angiograms are already sparse in the image domain. They can be further sparsified through finite-differences. Therefor...

Colorectal cancer (CRC) is the second most common cause of cancer death in the western world, with a high lifetime incidence of 6%. The optimization of surgical techniques, introduction of neoadjuvant therapies and recent developments in diagnostic imaging modalities, contributed to the significant decrease of the mortality by 20% in the last years...

Diffuse optical spectroscopy imaging (DOSI) has shown great potential for the early detection of non-responding tumors during neoadjuvant chemotherapy in breast cancer, already one day after therapy starts. Patients with rectal cancer receive similar chemotherapy treatment. The rectum geometry and tissue properties of healthy and tumor tissue in th...

The presence of significant forearm bone torsion might affect planning and evaluating treatment regimes in cerebral palsy patients. We aimed to evaluate the influence of longstanding wrist flexion, ulnar deviation, and forearm pronation due to spasticity on the bone geometries of radius and ulna. Furthermore, we aimed to model the hypothetical infl...

We discuss a new planning method for corrective osteotomy surgery without the need to make a CT scan of the contralateral bone. We use a statistical shape model to estimate the most likely relative position of two bone segments of an osteotomized bone. To investigate the added value of geometrical properties for planning, different geometrical feat...

The characterization of myocardial scar tissue in Late Gadolinium Enhancement (LGE) MRI volumes is hampered by the nonquantitative nature of MRI image intensities. Using the widely available Look-Locker (LL) sequence that images the heart using different inversion times a T1 map can be created per patient to calibrate the LGE datasets. However, due...

Characterization of myocardial scar has important diagnostic and prognostic value for treatment of post-infarction patients. Late gadolinium enhanced (LGE) MR visualizes myocardial scar as regions of hyper-enhanced signal intensity, however, the accuracy and reproducibility of scar characterization is impaired by the lack of an absolute measure in...

Background: The assessment of the joint space thickness is an important clinical parameter for diagnosing osteoarthritis. The accuracy of joint space thickness evaluation from radiographs is limited due to anatomical complexity of the wrist. We propose using distance maps estimated from 3-dimensional and 4-dimensional images reflecting joint space...

The purpose of this study is to gain a better understanding of the changes due to osteoarthritis (OA) occurring in the thumb carpometacarpal (CMC) joint by comparing quantitative geometrical measurements in computed tomography scans of healthy and pathological joints in various stages of OA. The measurements were (1) the subluxation of the metacarp...

First-pass cardiac MR perfusion (CMRP) imaging allows identification of hypo-perfused areas in the myocardium and therefore helps in early detection of coronary artery disease (CAD). However, its efficacy is often limited by respiratory motion artifacts, especially in stress-induced sequences. These distortions lead to unreliable estimates of perfu...

First-pass cardiac MR perfusion (CMRP) imaging allows identification of hypo-perfused areas in the myocardium and therefore helps in early detection of coronary artery disease (CAD). However, its efficacy is often limited by respiratory motion artifacts, especially in stress-induced sequences. These distortions lead to unreliable estimates of perfu...

We present an extension of the symmetric ICP algorithm that is unbiased for an arbitrary number (N ≥ 2) of shapes, using rigid transformations and scaling. The method does not require the selection of a reference shape or registration order and hence it is unbiased towards any of the registered shapes. The functional to be minimized is non-linear i...

In this paper a novel groupwise registration algorithm is proposed for the unbiased registration of a large number of densely sampled point clouds. The method fits an evolving mean shape to each of the example point clouds thereby minimizing the total deformation. The registration algorithm alternates between a computationally expensive, but parall...

Fluorescence loss in photobleaching (FLIP) is a method to study compartment connectivity in living cells. A FLIP sequence is obtained by alternatively bleaching a spot in a cell and acquiring an image of the complete cell. Connectivity is estimated by comparing fluorescence signal attenuation in different cell parts. The measurements of the fluores...

Direct imaging of ligament damage in the wrist remains a challenge. Still, such damage can be assessed indirectly through the analysis of changes in wrist pose and motion pattern. For this purpose we built a statistical reference model that describes healthy motion patterns. We show that such a model can also be used to detect and quantify patholog...

The trapeziometacarpal joint enables the prehensile function of the thumb. Unfortunately, this joint is vulnerable to osteoarthritis (OA) that typically affects the local shape of the trapezium. A novel, local statistical shape model is defined that employs a differentiable locality measure based on the weighted variance of point coordinates per mo...

The purpose of this study was to measure changes in scaphoid kinematics after division of scaphotrapeziotrapezoidal ligaments, with the intention of determining a clinical measure that could be detected by computed tomography. Twelve freshly frozen cadaver upper extremities were marked with tantalum beads and fixed in positions of neutral, 30° exte...

Diagnosing of injuries of the wrist bones is problematic due to a highly complex and variable geometry. knowledge of variations of healthy bone shapes is essential to detect wrist pathologies, developing prosthetics and investigating biomechanical properties of the wrist joint. In previous literature various methods have been proposed to classify d...

The design of most ulnar head implants is currently not based on studies of anatomical variations. To enable prosthesis design based on anatomical features, a method is developed for the detection of the ulna surface that articulates with the radius head. The articulating surface is detected by combining partial articulating ulna surfaces detected...

Comparing wrist shapes of different individuals requires alignment of these wrists into the same pose. Unconstrained registration of the carpal bones results in anatomically nonfeasible wrists. In this paper, we propose to constrain the registration using the shapes of adjacent bones, by keeping the width of the gap between adjacent bones constant....

Current diagnosis of wrist joint problems is hampered by poor understanding of wrist joint functioning. To gain insight into the relationship between function and anatomy we aim at building a statistical shape model of the wrist. As a basis for the statistical model we intend to use CT scans of different individuals that are mutually registered to...

Small mobile robots typically have little on-board processing power for time-consuming vision algorithms. Here we show how they can quickly extract very dense yet highly useful information from color images. A single pass through all pixels of an image serves to segment it into color-dependent regions and to compactly represent it by a short list o...

Carpal instability occurs when the wrist bones assume a pathological posture, e.g. due to ligament rupture as a result of trauma. Ligament rupture cannot be diagnosed reliably directly, as current medical imaging modalities do not provide sufficient soft-tissue contrast (X-ray, CT) or lack a sufficiently high resolution (CT, MRI). Ligament rupture,...